N-Skatyltryptamines—Dual 5-HT6R/D2R Ligands with Antipsychotic and Procognitive Potential

A series of N-skatyltryptamines was synthesized and their affinities for serotonin and dopamine receptors were determined. Compounds exhibited activity toward 5-HT_1A, 5-HT_2A, 5-HT₆, and D₂ receptors. Substitution patterns resulting in affinity/activity switches were identified and studied using homology modeling. Chosen hits were screened to determine their metabolism, permeability, hepatotoxicity, and CYP inhibition. Several D₂ receptor antagonists with additional 5-HT₆R antagonist and agonist properties were identified. The former combination resembled known antipsychotic agents, while the latter was particularly interesting due to the fact that it has not been studied before. Selective 5-HT₆R antagonists have been shown previously to produce procognitive and promnesic effects in several rodent models. Administration of 5-HT₆R agonists was more ambiguous—in naive animals, it did not alter memory or produce slight amnesic effects, while in rodent models of memory impairment, they ameliorated the condition just like antagonists. Using the identified hit compounds 15 and 18, we tried to sort out the difference between ligands exhibiting the D₂R antagonist function combined with 5-HT₆R agonism, and mixed D₂/5-HT₆R antagonists in murine models of psychosis.     

All‐Solid‐State Ion Selective and All‐Solid‐State Reference Electrodes

This paper is aiming to give a brief overview of recent research in the field of all‐solid‐state, internal solution free, ion‐selective electrodes and reference electrodes, employing conducting polymers or nano‐/microstructures as solid contacts beneath the polymeric, ion‐selective or reference membranes. The emphasis is on papers published in the last five years (after 2006). According to the papers published, poly(3‐octylthiophene) conducting polymer transducers offer highly reliable sensors for various applications, involving demanding analytical approaches and miniature sensors. On the other hand, the search for alternative materials continues: the sensors obtained by placing nano‐/microstructures (conducting polymers but also other materials, like, e.g., carbon nanotubes) underneath the receptor membrane are intensively tested. The recent years have also shown how useful the application of advanced instrumental methods is for the investigation of processes occurring within all‐solid‐state ion‐selective electrodes.     

Distinguishing between polymorphic forms of linezolid by solid-phase electronic and vibrational circular dichroism

For the first time two crystalline forms of the same compound (linezolid polymorphs) were investigated by means of the solid-phase ECD and VCD spectra. The ECD spectra show distinct differences and the band at 221 nm serves as a diagnostic one because it is present in form II but absent in form III. The VCD spectra strongly differ in the diagnostic carbonyl absorption range exhibiting two relatively strong bands of opposite signs.     

An assessment of various powdered baby formulas by conventional methods (DSC) or FT-IR spectroscopy

Milk components are assumed to be uniformly distributed in a concentrate whilst it is being dried. During milk powder production, these components are redistributed in the drying droplets and the powder surface composition is significantly different from that of the bulk of it. The objective of this article was to analyze and compare phase transitions of powdered baby formulas as well as to make a study of their FT-IR spectra. Food powders of different composition were tested by a differential scanning calorimeter (DSC, TA Instruments Q 200) with a normal pressure cell and a System 2000 spectrophotometer. Significant differences were observed in the shape of curves of the mixtures and the agglomerates. The observed phase transitions in powders depended on fat content. Characteristic peaks of melting lactose were observed in the curves of the powdered baby formulas. The IR spectra proved to be useful in determining adulteration of baby formulas. Both methods were complimentary during a thorough evaluation of these food powders.     

Expression of GD3 synthase modifies ganglioside profile and increases migration of MCF-7 breast cancer cells

B- and c-series of gangliosides are over-expressed in neuro-ectoderm-related cancers, including breast cancer. It has been shown that G_D3 ganglioside is over-expressed in about 50% of invasive ductal breast carcinoma and the G_D3 synthase (GD3S) gene displays higher expression among estrogen receptor (ER) negative breast tumors. We previously showed that GD3S expression in MDA-MB-231 breast cancer cells induces the expression of G_D2 and increased cell proliferation and migration via a G_D2-dependent activation of c-Met receptor. Here, we show that in ER-positive MCF-7 breast cancer cells, GD3S expression resulted in an increase of G_D1b, which was associated with a decrease of G_M1a and G_M2. Meanwhile, GD3S expressing MCF-7 cells exhibited an increased migration without any modification of proliferation rate. Therefore, GD3S expression can result in different modifications of both ganglioside profiles and cell phenotypes depending on breast cell types.     

Self‐assembly of long‐chain quaternary ammonium cations in a hybrid inorganic–organic material with one‐dimensional polymeric tribromidoplumbate(II)

catena‐Poly[benzyldecyldimethylammonium [plumbate(II)‐tri‐μ‐bromido]], {(C₁₉H₃₄N)[PbBr₃]}_n, crystallizes as an inorganic–organic hybrid following monoclinic space‐group symmetry P2₁/c. The structure consists of extended chains running along the [001] direction and built of [PbBr₃]⁻ units. These inorganic chains are separated by interdigitated ammonium cations which form hydrophilic layers through weak C—H...Br interactions. The architecture is essentialy the same as found for n‐alkylbenzyldimethylammonium bromides.     

HS⇄LS transition in iron(II) two-dimensional coordination networks containing tris(tetrazol-1-ylmethyl)methane as triconnected building block

Novel tripodal ligand 1,1',1'-tris(tetrazol-1-ylmethyl)methane (111tz) and products of its reactions with perchlorate as well as with tetrafluoroborate salts of iron(II) are presented. The isostructural complexes, [Fe(111tz)?](ClO?)? and [Fe(111tz)?](BF?)?, were isolated as two-dimensional (2D) coordination networks revealing a honeycomb-like pattern with cages occupied by disordered anions. 111tz molecules act as a tridentate ligand bridging three adjacent Fe(II) ions, and the nitrogen N4 atom of six tetrazole rings (tz) is placed in octahedron vertices of FeN? chromophores. The complexes, crystallizing in the P3 space group, were characterized by variable-temperature single-crystal X-ray diffraction and variable-temperature magnetic susceptibility measurements. Variable-temperature magnetic susceptibility measurements show that both systems undergo abrupt and complete spin transition with T(1/2)(↑) = T(1/2)(↓) = 176 K for perchlorate and T(1/2)(↑) = 193.8 and T(1/2)(↓) = 192.8 K for the tetrafluoroborate analogue. Change of spin state in both complexes is accompanied by a thermochromic effect. The HS→LS transition in [Fe(111tz)?](ClO?)? involves shortening of the Fe-N4 bond lengths from 2.171(2) ? (293 K) to 2.002(1) ? (100 K). In [Fe(111tz)?](BF?)?, lowering of temperature from 293 to 100 K is accompanied by shortening of the Fe-N4 distances from 2.179(2) to 1.987(2) ?, respectively. Perchlorate in [Fe(111tz)?](ClO?)? or tetrafluoroborate anions in [Fe(111tz)?](BF?)? are engaged in the formation of intermolecular contacts within as well as with the neighboring 2D layer.     

Algebraic proof theory for substructural logics: Cut-elimination and completions

We carry out a unified investigation of two prominent topics in proof theory and order algebra: cut-elimination and completion, in the setting of substructural logics and residuated lattices.We introduce the substructural hierarchy — a new classification of logical axioms (algebraic equations) over full Lambek calculus FL, and show that a stronger form of cut-elimination for extensions of FL and the MacNeille completion for subvarieties of pointed residuated lattices coincide up to the level N₂ in the hierarchy. Negative results, which indicate limitations of cut-elimination and the MacNeille completion, as well as of the expressive power of structural sequent calculus rules, are also provided.Our arguments interweave proof theory and algebra, leading to an integrated discipline which we call algebraic proof theory.     

Optimizing the analytical performance and construction of ion-selective electrodes with conducting polymer-based ion-to-electron transducers

All-solid-state ion-selective electrodes that use a conducting polymer as the ion-to-electron transducer have emerged as one of the most promising classes of all-solid-state potentiometric sensors in recent years. This is largely because it has many analytical advantages, including high response stability, which is unique in the field of internal-solution-free ion-selective electrodes. This paper reviews the considerable progress that has been made in this area of sensing in recent years, in terms of detection limits, selectivity coefficients and novel construction methods.     

Chiral ytterbium complex-catalyzed direct asymmetric aldol-Tishchenko reaction: synthesis of anti-1,3-diols

The asymmetric aldol-Tishchenko reaction of aromatic aldehydes with aliphatic and aromatic ketones has been developed as an efficient strategy for the synthesis of anti-1,3-diols in good yield with high diastereocontrol and good levels of enantioselectivity. This domino-type reaction is catalyzed by a chiral ytterbium complex that promotes both the aldol reaction through enolization of the carbonyl compound and the Evans-Tishchenko reduction of the aldol intermediate. The stereochemistry of the resulting diols is also investigated and finally proved by using CD techniques.